geppy
commented
10 years ago It looks like a <core-menu> is created+inserted in between 1 and 1A+1B that has a height set (to the height of the collapsed 1A+1B submenu items) with overflow hidden.
Given that a <core-menu> is created+inserted, Is nesting submenus not intended?
When you nested` in IE9, it has various failure modes. Here's a barebones example of nested submenus (it's in branch "nested-submenus" if you check it out).
In that example, if you open up submenu 1, then 1A, only the first item from 1A shows up (it has three children, all
<core-item>s).If you open up 1, then 1B, none of the children show up (there should be three
<core-item>s).I can put the example up on a server if checking it out is a pain.